Plants and animals have yielded a number of chemical molecules having useful biological activity (e.g., anti-tumor activity). Particularly rich sources of biologically active chemicals are marine organisms, which comprise over half a million species. Marine organisms have been found to produce a variety of metabolic often having unprecedented chemical structures.
In recent years, an increasing number of natural products extracted from marine organisms have been reported to exhibit a variety of biological activities such as antimicrobial, antiviral, antifungal and anticancer activities. These include peptides, polyethers, alkaloids, prostanoids, and the like. Such compounds have been obtained from sponges, octocorals, algae, tunicates, nuclibranches, bryozoans and marine bacteria.
In particular, a number of anti-tumor and anti-fungal compounds have been extracted from marine life. For example, U.S. Pat. No. 4,729,996 discloses anti-tumor imidazole ring compounds isolated from the marine sponges Teichaxinella morchella and Ptioocaulis walpersi. U.S. Pat. No. 4,808,590 discloses nitrogen containing cyclic compounds isolated having antiviral, anti-tumor, and antifungal properties, isolated from the marine sponge Theoneloa sp. Similarly, U.S. Pat. No. 4,866,084 discloses bisindole alkaloids extracted from the marine sponge Spongosorites ruetzleri useful in treating certain classes of tumors, while U.S. Pat. No. 4,970,226 discloses bis-indole imidazole alkaloids and derivatives isolated from the marine sponge Spongosorites sp. which exhibit useful anti-tumor and antimicrobial properties.
Marine sponges, in particular, have proven to be a rich resource for biologically active compounds (see, e.g., Scheuer, P. J. (ed.) (1978-1983) Marine Natural Products, Chemical and Biological Perspectives Vol. I-V, Academic Press, New York; Faulkner (1977) Tetrahedron, 33: 1421; Faulkner (1984) Nat, Prod. Rep. 1: 551; Faulkner (1986) Nat, Prod. Rep. 3: 1; Faulkner (1987) Nat, Prod. Rep. 4: 539; Faulkner (1988) Nat, Prod. Rep. 5: 613; Faulkner (1990) Nat, Prod. Rep. 7: 269; Faulkner (1991) Nat, Prod. Rep. 7: 269; Faulkner (1992) Nat, Prod. Rep. 9: 323; Faulkner (1993) Nat, Prod. Rep. 10: 497; Faulkner (1994) Nat, Prod. Rep. 1 1: 355; Faulkner (1954) Nat, Prod. Rep. 12: 223; Faulkner (1996) Nat, Prod. Rep. 13: 75; Faulkner (1997) Nat, Prod. Rep. 14: 256; and Faulkner (1985) J. Am. Chem. Soc. 107: 4796-4798). However there exist literally thousands of species of marine sponges and these organisms are only beginning to be explored.